1.
ChemSpider
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ChemSpider is a database of chemicals. ChemSpider is owned by the Royal Society of Chemistry, the database contains information on more than 50 million molecules from over 500 data sources including, Each chemical is given a unique identifier, which forms part of a corresponding URL. This is an approach to develop an online chemistry database. The search can be used to widen or restrict already found results, structure searching on mobile devices can be done using free apps for iOS and for the Android. The ChemSpider database has been used in combination with text mining as the basis of document markup. The result is a system between chemistry documents and information look-up via ChemSpider into over 150 data sources. ChemSpider was acquired by the Royal Society of Chemistry in May,2009, prior to the acquisition by RSC, ChemSpider was controlled by a private corporation, ChemZoo Inc. The system was first launched in March 2007 in a release form. ChemSpider has expanded the generic support of a database to include support of the Wikipedia chemical structure collection via their WiChempedia implementation. A number of services are available online. SyntheticPages is an interactive database of synthetic chemistry procedures operated by the Royal Society of Chemistry. Users submit synthetic procedures which they have conducted themselves for publication on the site and these procedures may be original works, but they are more often based on literature reactions. Citations to the published procedure are made where appropriate. They are checked by an editor before posting. The pages do not undergo formal peer-review like a journal article. The comments are moderated by scientific editors. The intention is to collect practical experience of how to conduct useful chemical synthesis in the lab, while experimental methods published in an ordinary academic journal are listed formally and concisely, the procedures in ChemSpider SyntheticPages are given with more practical detail. Comments by submitters are included as well, other publications with comparable amounts of detail include Organic Syntheses and Inorganic Syntheses

2.
Chemical formula
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These are limited to a single typographic line of symbols, which may include subscripts and superscripts. A chemical formula is not a name, and it contains no words. Although a chemical formula may imply certain simple chemical structures, it is not the same as a full chemical structural formula. Chemical formulas can fully specify the structure of only the simplest of molecules and chemical substances, the simplest types of chemical formulas are called empirical formulas, which use letters and numbers indicating the numerical proportions of atoms of each type. Molecular formulas indicate the numbers of each type of atom in a molecule. For example, the formula for glucose is CH2O, while its molecular formula is C6H12O6. This is possible if the relevant bonding is easy to show in one dimension, an example is the condensed molecular/chemical formula for ethanol, which is CH3-CH2-OH or CH3CH2OH. For reasons of structural complexity, there is no condensed chemical formula that specifies glucose, chemical formulas may be used in chemical equations to describe chemical reactions and other chemical transformations, such as the dissolving of ionic compounds into solution. A chemical formula identifies each constituent element by its chemical symbol, in empirical formulas, these proportions begin with a key element and then assign numbers of atoms of the other elements in the compound, as ratios to the key element. For molecular compounds, these numbers can all be expressed as whole numbers. For example, the formula of ethanol may be written C2H6O because the molecules of ethanol all contain two carbon atoms, six hydrogen atoms, and one oxygen atom. Some types of compounds, however, cannot be written with entirely whole-number empirical formulas. An example is boron carbide, whose formula of CBn is a variable non-whole number ratio with n ranging from over 4 to more than 6.5. When the chemical compound of the consists of simple molecules. These types of formulas are known as molecular formulas and condensed formulas. A molecular formula enumerates the number of atoms to reflect those in the molecule, so that the formula for glucose is C6H12O6 rather than the glucose empirical formula. However, except for very simple substances, molecular chemical formulas lack needed structural information, for simple molecules, a condensed formula is a type of chemical formula that may fully imply a correct structural formula. For example, ethanol may be represented by the chemical formula CH3CH2OH

3.
Density
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The density, or more precisely, the volumetric mass density, of a substance is its mass per unit volume. The symbol most often used for density is ρ, although the Latin letter D can also be used. Mathematically, density is defined as mass divided by volume, ρ = m V, where ρ is the density, m is the mass, and V is the volume. In some cases, density is defined as its weight per unit volume. For a pure substance the density has the numerical value as its mass concentration. Different materials usually have different densities, and density may be relevant to buoyancy, purity, osmium and iridium are the densest known elements at standard conditions for temperature and pressure but certain chemical compounds may be denser. Thus a relative density less than one means that the floats in water. The density of a material varies with temperature and pressure and this variation is typically small for solids and liquids but much greater for gases. Increasing the pressure on an object decreases the volume of the object, increasing the temperature of a substance decreases its density by increasing its volume. In most materials, heating the bottom of a results in convection of the heat from the bottom to the top. This causes it to rise relative to more dense unheated material, the reciprocal of the density of a substance is occasionally called its specific volume, a term sometimes used in thermodynamics. Density is a property in that increasing the amount of a substance does not increase its density. Archimedes knew that the irregularly shaped wreath could be crushed into a cube whose volume could be calculated easily and compared with the mass, upon this discovery, he leapt from his bath and ran naked through the streets shouting, Eureka. As a result, the term eureka entered common parlance and is used today to indicate a moment of enlightenment, the story first appeared in written form in Vitruvius books of architecture, two centuries after it supposedly took place. Some scholars have doubted the accuracy of this tale, saying among other things that the method would have required precise measurements that would have been difficult to make at the time, from the equation for density, mass density has units of mass divided by volume. As there are units of mass and volume covering many different magnitudes there are a large number of units for mass density in use. The SI unit of kilogram per metre and the cgs unit of gram per cubic centimetre are probably the most commonly used units for density.1,000 kg/m3 equals 1 g/cm3. In industry, other larger or smaller units of mass and or volume are often more practical, see below for a list of some of the most common units of density

4.
Vapor pressure
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Vapor pressure or equilibrium vapor pressure is defined as the pressure exerted by a vapor in thermodynamic equilibrium with its condensed phases at a given temperature in a closed system. The equilibrium vapor pressure is an indication of a liquids evaporation rate and it relates to the tendency of particles to escape from the liquid. A substance with a vapor pressure at normal temperatures is often referred to as volatile. The pressure exhibited by vapor present above a surface is known as vapor pressure. As the temperature of a liquid increases, the energy of its molecules also increases. As the kinetic energy of the molecules increases, the number of molecules transitioning into a vapor also increases, the vapor pressure of any substance increases non-linearly with temperature according to the Clausius–Clapeyron relation. The atmospheric pressure boiling point of a liquid is the temperature at which the pressure equals the ambient atmospheric pressure. With any incremental increase in temperature, the vapor pressure becomes sufficient to overcome atmospheric pressure. Bubble formation deeper in the liquid requires a pressure, and therefore higher temperature. More important at shallow depths, is the temperature required to start bubble formation. The surface tension of the wall lead to an overpressure in the very small initial bubbles. Thus, thermometer calibration should not rely on the temperature in boiling water, the vapor pressure that a single component in a mixture contributes to the total pressure in the system is called partial pressure. Vapor pressure is measured in the units of pressure. The International System of Units recognizes pressure as a unit with the dimension of force per area. One pascal is one newton per square meter, experimental measurement of vapor pressure is a simple procedure for common pressures between 1 and 200 kPa. Most accurate results are obtained near the point of substances. Better accuracy is achieved when care is taken to ensure that the entire substance and this is often done, as with the use of an isoteniscope, by submerging the containment area in a liquid bath. Very low vapor pressures of solids can be measured using the Knudsen effusion cell method, the Antoine equation is a mathematical expression of the relation between the vapor pressure and the temperature of pure liquid or solid substances

5.
Pyrethroid
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A pyrethroid is an organic compound similar to the natural pyrethrins produced by the flowers of pyrethrums. Pyrethroids now constitute the majority of commercial household insecticides, pyrethroids are axonic excitoxins, the toxic effects of which are mediated through preventing the closure of the voltage-gated sodium channels in the axonal membranes. The sodium channel is a protein with a hydrophilic interior. When the toxin keeps the channels in their state, the nerves cannot repolarize, leaving the axonal membrane permanently depolarized. Pyrethroids can be combined with the synergist piperonyl butoxide, an inhibitor of key microsomal cytochrome P450 enzymes from metabolizing the pyrethroid. Pyrethroids were introduced by a team of Rothamsted Research scientists following the elucidation of the structures of pyrethrin I and II by Hermann Staudinger, the pyrethroids represented a major advancement in the chemistry that would synthesize the analog of the natural version found in pyrethrum. Its insecticidal activity has relatively low toxicity and an unusually fast biodegradation. Their development coincided with the identification of problems with DDT use and their work consisted firstly of identifying the most active components of pyrethrum, extracted from East African chrysanthemum flowers and long known to have insecticidal properties. Pyrethrum rapidly knocks down flying insects but has negligible persistence — which is good for the environment, pyrethroids are essentially chemically stabilized forms of natural pyrethrum and belong to IRAC MoA group 3. The first-generation pyrethroids, developed in the 1960s, include bioallethrin, tetramethrin, resmethrin and bioresmethrin and they are more active than the natural pyrethrum but are unstable in sunlight. Activity of pyrethrum and 1st-generation pyrethroids is often enhanced by addition of the synergist piperonyl butoxide, with the 91/414/EEC review, many 1st-generation compounds have not been included on Annex 1, probably because the market is simply not big enough to warrant the costs of re-registration. By 1974, the Rothamsted team had discovered a generation of more persistent compounds notably. They are substantially more resistant to degradation by light and air, thus making them suitable for use in agriculture, over the subsequent decades these derivatives were followed with other proprietary compounds such as fenvalerate, lambda-cyhalothrin and beta-cyfluthrin. Most patents have now expired, making these compounds cheap and therefore popular, the earliest pyrethoids are related to pyrethrin I and II by changing the alcohol group of the ester of chrysanthemic acid. This relatively modest change can lead to substantially altered activities, for example, the 5-benzyl-3-furanyl ester called resmethrin is only weakly toxic to mammals but is 20–50 times more effective than natural pyrethrum and is also readily biodegraded. Other commercially important esters include tetramethrin, allethrin, phenothrin, barthrin, dimethrin, another family of pyrethroids have altered acid fragment together with altered alcohol components. These require more elaborate organic synthesis, members of this extensive class include the dichlorovinyl and dibromovinyl derivatives. Still others are tefluthrin, fenpropathrin, and bioethanomethrin, pyrethroids are toxic to beneficial insects such as bees and dragonflies, and to fish and other aquatic organisms

6.
Insecticide
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An insecticide is a substance used to kill insects. They include ovicides and larvicides used against insect eggs and larvae, Insecticides are used in agriculture, medicine, industry and by consumers. Insecticides are claimed to be a factor behind the increase in agricultural 20th centurys productivity. Nearly all insecticides have the potential to significantly alter ecosystems, many are toxic to humans, Insecticides can be classified in two major groups, systemic insecticides, which have residual or long term activity, and contact insecticides, which have no residual activity. Furthermore, one can distinguish three types of insecticide, natural insecticides, such as nicotine, pyrethrum and neem extracts, made by plants as defenses against insects. Organic insecticides, which are chemical compounds, mostly working by contact. The mode of action describes how the pesticide kills or inactivates a pest and it provides another way of classifying insecticides. Mode of action is important in understanding whether an insecticide will be toxic to unrelated species, such as fish, birds, Insecticides are distinct from insect repellents, which do not kill. Systemic insecticides become incorporated and distributed throughout the whole plant. When insects feed on the plant, they ingest the insecticide, systemic insecticides produced by transgenic plants are called plant-incorporated protectants. For instance, a gene that codes for a specific Bacillus thuringiensis biocidal protein was introduced into corn, the plant manufactures the protein, which kills the insect when consumed. Contact insecticides are toxic to insects upon direct contact and these can be inorganic insecticides, which are metals and include arsenates, copper and fluorine compounds, which are less commonly used, and the commonly used sulfur. Contact insecticides can be organic insecticides, i. e. organic chemical compounds, synthetically produced, or they can be natural compounds like pyrethrum, neem oil etc. Contact insecticides usually have no residual activity, efficacy can be related to the quality of pesticide application, with small droplets, such as aerosols often improving performance. Many organic compounds are produced by plants for the purpose of defending the host plant from predation, a trivial case is tree rosin, which is a natural insecticide. Specific, the production of oleoresin by conifer species is a component of the response against insect attack. Many fragrances, e. g. oil of wintergreen, are in fact antifeedants, the technique has been expanded to include the use of RNA interference RNAi that fatally silences crucial insect genes. RNAi likely evolved as a defense against viruses, midgut cells in many larvae take up the molecules and help spread the signal

7.
Enantiomer
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A single chiral atom or similar structural feature in a compound causes that compound to have two possible structures which are non-superposable, each a mirror image of the other. Each member of the pair is termed an enantiomorph, the property is termed enantiomerism. The presence of multiple features in a given compound increases the number of geometric forms possible. Enantiopure compounds refer to samples having, within the limits of detection and they are sometimes called optical isomers for this reason. Enantiomer members often have different chemical reactions with other enantiomer substances, since many biological molecules are enantiomers, there is sometimes a marked difference in the effects of two enantiomers on biological organisms. Owing to this discovery, drugs composed of one enantiomer can be developed to enhance the pharmacological efficacy. An example is eszopiclone, which is enantiopure and therefore administered in doses that are exactly 1/2 of the older, in the case of eszopiclone, the S enantiomer is responsible for all the desired effects, while the other enantiomer seems to be inactive. A dose of 2 mg of zopiclone must be administered to produce the therapeutic effect as 1 mg of eszopiclone. In chemical synthesis of enantiomeric substances, non-enantiomeric precursors inevitably produce racemic mixtures, in the absence of an effective enantiomeric environment, separation of a racemic mixture into its enantiomeric components is impossible. The R/S system is an important nomenclature system for denoting distinct enantiomers, another system is based on prefix notation for optical activity, - and - or d- and l-. The Latin for left and right is laevus and dexter, respectively, left and right have always had moral connotations, and the Latin words for these are sinister and rectus. The English word right is a cognate of rectus and this is the origin of the D, L and S, R notations, and the employment of prefixes levo- and dextro- in common names. Most compounds that one or more asymmetric carbon atoms show enantiomerism. There are a few compounds that do have asymmetric carbon atoms. An example of such an enantiomer is the sedative thalidomide, which was sold in a number of countries across the world from 1957 until 1961 and it was withdrawn from the market when it was found to cause of birth defects. One enantiomer caused the desirable effects, while the other, unavoidably present in equal quantities. The herbicide mecoprop is a mixture, with the --enantiomer possessing the herbicidal activity. Another example is the antidepressant drugs escitalopram and citalopram, citalopram is a racemate, escitalopram is a pure enantiomer

8.
Fenvalerate
–
It is a mixture of four optical isomers which have different insecticidal activities. The 2-S alpha configuration, known as esfenvalerate, is the most insecticidally active isomer, fenvalerate consists of about 23% of this isomer. Fenvalerate is an insecticide of moderate mammalian toxicity, in laboratory animals, central nervous system toxicity is observed following acute or short-term exposure. Fenvalerate has applications against a range of pests. Residue levels are minimized by low application rates, fenvalerate is most toxic to bees and fish. It is found in some emulsifiable concentrates, ULV, wettable powders, slow release formulations, insecticidal fogs and it is most commonly used to control insects in food, feed, and cotton products, and for the control of flies and ticks in barns and stables. Fenvalerate does not affect plants, but is active for a period of time. Fenvalerate may irritate the skin and eyes on contact, and is harmful if swallowed

9.
Pest control
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Pest control refers to the regulation or management of a species defined as a pest, and can be perceived to be detrimental to a persons health, the ecology or the economy. A practitioner of pest control is called an exterminator, Pest control is at least as old as agriculture, as there has always been a need to keep crops free from pests. In order to maximize production, it is advantageous to protect crops from competing species of plants. Techniques such as rotation, companion planting, and the selective breeding of pest-resistant cultivars have a long history. In the UK, following concern about animal welfare, humane pest control, for instance, with the urban red fox which territorial behaviour is used against the animal, usually in conjunction with non-injurious chemical repellents. In rural areas of Britain, the use of firearms for pest control is quite common, chemical pesticides date back 4,500 years, when the Sumerians used sulfur compounds as insecticides. The Rig Veda, which is about 4,000 years old, in the 20th century, the discovery of several synthetic insecticides, such as DDT, and herbicides boosted this development. Many pests have only become a problem as a result of the actions by humans. Modifying these actions can often reduce the pest problem. In the United States, raccoons caused a nuisance by tearing open refuse sacks, many householders introduced bins with locking lids, which deterred the raccoons from visiting. House flies tend to accumulate wherever there is activity and live in close association with people all over the world especially where food or food waste is exposed. Similarly, seagulls have become pests at many seaside resorts, tourists would often feed the birds with scraps of fish and chips, and before long, the birds would rely on this food source and act aggressively towards humans. Living organisms evolve and increase their resistance to biological, chemical, physical or any form of control. Perhaps as far ago as 3000BC in Egypt, cats were being used to control pests of grain such as rodents. In 1939/40 a survey discovered that cats could keep a population of rats down to a low level. However, if the rats were cleared by trapping or poisoning, ferrets were domesticated at least by 500 AD in Europe, being used as mousers. Mongooses have been introduced into homes to control rodents and snakes, biological pest control is the control of one through the control and management of natural predators and parasites. For example, mosquitoes are often controlled by putting Bt Bacillus thuringiensis ssp. israelensis, the treatment has no known negative consequences on the remaining ecology and is safe for humans to drink

10.
Carbamate
–
A carbamate is an organic compound derived from carbamic acid. A carbamate group, carbamate ester, and carbamic acids are functional groups that are inter-related structurally, carbamate esters are also called urethanes. Carbamic acids are derived from amines, R2NH + CO2 → R2NCO2H Carbamic acid is about as acidic as acetic acid, n-terminal amino groups of valine residues in the α- and β-chains of deoxyhemoglobin exist as carbamates. They help to stabilise the protein, when it becomes deoxyhemoglobin and this stabilizing effect should not be confused with the Bohr effect. The ε-amino groups of the residues in urease and phosphotriesterase also feature carbamate. The carbamate derived from aminoimidazole is an intermediate in the biosynthesis of inosine, carbamoyl phosphate is generated from carboxyphosphate rather than CO2. Perhaps the most important carbamate is the one involved in the capture of CO2 by plants since this process is necessary for their growth, the enzyme ribulose 1, 5-bisphosphate carboxylase/oxygenase fixes a molecule of carbon dioxide as phosphoglycerate in the Calvin cycle. At the active site of the enzyme, a Mg2+ ion is bound to glutamate and aspartate residues as well as a lysine carbamate. The carbamate is formed when an uncharged lysine side chain near the ion reacts with a carbon dioxide molecule from the air, which renders it charged. The so-called carbamate insecticides feature the carbamate ester functional group, included in this group are aldicarb, carbofuran, carbaryl, ethienocarb, fenobucarb, oxamyl, and methomyl. These insecticides kill insects by reversibly inactivating the enzyme acetylcholinesterase, the organophosphate pesticides also inhibit this enzyme, although irreversibly, and cause a more severe form of cholinergic poisoning. Fenoxycarb has a group but acts as a juvenile hormone mimic. The insect repellent icaridin is a substituted carbamate, polyurethanes contain multiple carbamate groups as part of their structure. The urethane in the name refers to these carbamate groups. In contrast, the commonly called urethane, ethyl carbamate, is neither a component of polyurethanes. Urethanes are usually formed by reaction of an alcohol with an isocyanate, commonly, urethanes made by a non-isocyanate route are called carbamates. Polyurethane polymers have a range of properties and are commercially available as foams, elastomers. Typically, polyurethane polymers are made by combining diisocyanates, e. g. Urethane was once produced commercially in the United States as an antineoplastic agent and it was found to be toxic and largely ineffective

11.
Aldicarb
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Aldicarb is a carbamate insecticide which is the active substance in the pesticide Temik. It is effective against thrips, aphids, spider mites, lygus, fleahoppers, and leafminers, aldicarb is a cholinesterase inhibitor which prevents the breakdown of acetylcholine in the synapse. In case of poisoning, the victim dies of respiratory failure. Aldicarb is one of the most widely used internationally, and is also one of the most environmentally toxic. Aldicarb poisoning from agricultural runoff has led to the destruction of healthy ecosystems. Poisoning from this pesticide is also believed to be linked to high rates in communities located around the Aral Sea. Its high level of solubility restricts its use in areas where the water table is close to the surface. In the United States, aldicarb was approved by the USEPA for use by professional pesticide applicators on a variety of crops, including cotton, beans and it is not approved for household use. EPA started limiting the main aldicarb pesticide, Temik 15G, in 2010, discontinuation of the use on citrus and potatoes began in 2012, with a complete phase out of the product expected by 2018. A new aldicarb pesticide named AgLogic 15G, was approved by the EPA in December 2011 and is said to be entering the market in 2015 and it will be registered for use on cotton, dry beans, peanuts, soybeans, sugar beets, and sweet potatoes. Tres Pasitos, a mouse, rat, and roach killer that contains high concentrations of aldicarb, has been imported into the United States from Mexico. The product is highly toxic to animals and people, and according to the EPA should never be used in home, aldicarb is classified as an extremely hazardous substance in the United States as defined in Section 302 of the U. S. Emergency Planning and Community Right-to-Know Act, and is subject to reporting requirements by facilities which produce, store. Aldicarb is manufactured by Bayer CropScience, but was owned and produced by Union Carbide. Union Carbides agricultural chemicals division was sold to Rhône-Poulenc, later, Aventis Cropscience was formed from Hoechst AG and Rhone-Poulenc Agrochemical, which lasted until Bayer acquired it in 2002. In November 2009, corn treated with Temik was placed in and around peanut fields in Eastland County, Texas, the corn was eaten by feral hogs, deer, and other animals, prompting the Texas Parks and Wildlife Department to issue a hunting ban. Aldicarb is a cholinesterase inhibitor, causing rapid accumulation of acetylcholine at the synaptic cleft. It is widely used to study cholinergic neurotransmission in simple systems such as the nematode C. elegans, exposure to high amounts of aldicarb can cause weakness, blurred vision, headache, nausea, tearing, sweating, and tremors in humans

12.
Bendiocarb
–
Bendiocarb is an acutely toxic carbamate insecticide used in public health and agriculture and is effective against a wide range of nuisance and disease vector insects. Many bendiocarb products are or were sold under the tradenames Ficam and Turcam and it is one of 12 insecticides recommended by the World Health Organization for use in malaria control. Bendiocarb is not considered to be carcinogenic, but it is acutely toxic, like other carbamates, it reversibly inhibits acetylcholinesterase, an enzyme required for normal transmission of nerve impulses. Bendiocarb binds to the site of this enzyme leading to an accumulation of acetylcholine. Bendiocarb was invented in 1971 and was first introduced into the market by Fisons Ltd. It is currently marketed by Bayer CropScience and Kuo Ching under various names, Ficam, Dycarb, Garvox, Turcam, Niomil, Seedox, Tattoo Bendiocarb is highly toxic to birds. In mammalian tissue, carbamates are generally excreted rapidly and do not accumulate, facts, Bendiocarb U. S. EPA, September 1999. Accessed August 2007 Compendium of Pesticide Common Names bendiocarb, Alan Wood, Justis Publishing Limited, London

13.
Carbaryl
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Carbaryl is a chemical in the carbamate family used chiefly as an insecticide. It is a crystalline solid commonly sold under the brand name Sevin. Union Carbide discovered carbaryl and introduced it commercially in 1958, Bayer purchased Aventis CropScience in 2002, a company that included Union Carbide pesticide operations. It remains the third-most-used insecticide in the United States for home gardens, commercial agriculture, about 11 million kilograms were applied to U. S. farm crops in 1976. As a veterinary drug, it is known as carbaril, carbaryl is produced by treating methyl isocyanate with 1-naphthol. Alternatively, 1-naphthol is reacted with phosgene to synthesize its chloroformate, in comparison, the latter synthesis uses exactly the same reagents, but in a different sequence. This synthesis avoids the preparation of methyl isocyanate, and the comparison is used as a case study in green chemistry. However, the second synthesis still uses phosgene, which is toxic and reacts with water, and methylamine, carbamate insecticides are slowly reversible inhibitors of the enzyme acetylcholinesterase. They resemble acetylcholine, but the enzyme undergoes the final hydrolysis step very slowly compared with the acetylated enzyme generated by acetylcholine. They interfere with the nervous system and cause death because the effects of the neurotransmitter acetylcholine cannot be terminated by carbamoylated acetylcholinesterase. The development of the carbamate insecticides has been called a breakthrough in pesticides. The carbamates do not have the persistence of chlorinated pesticides, although toxic to insects, carbaryl is detoxified and eliminated rapidly in vertebrates. It is neither concentrated in fat nor secreted in milk, so is favored for food crops and it is the active ingredient in Carylderm shampoo used to combat head lice until infestation is eliminated. Carbaryl kills both targeted and beneficial insects, as well as crustaceans, although approved for more than 100 crops in the US, carbaryl is illegal in several countries, including the United Kingdom, Austria, Denmark, Sweden, Iran, Germany, and Angola. Carbaryl is often produced using methyl isocyanate as an intermediary, a leak of MIC used in the production of carbaryl caused the Bhopal disaster, the largest industrial accident in history. Carbaryl is an inhibitor and is toxic to humans. It is classified as a human carcinogen by the United States Environmental Protection Agency The oral LD50 is 250 to 850 mg/kg for rats and 100 to 650 mg/kg for mice

14.
Carbofuran
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Carbofuran is one of the most toxic carbamate pesticides. It is marketed under the trade names Furadan, by FMC Corporation and Curater and it is used to control insects in a wide variety of field crops, including potatoes, corn and soybeans. It is an insecticide, which means that the plant absorbs it through the roots. Carbofuran also has activity against pests. S. The main global producer is the FMC Corporation, Carbofuran exhibits toxicity mediated by the same mechanism as that of the notorious V-series nerve agents and presents a risk to human health. It is classified as a hazardous substance in the United States as defined in Section 302 of the U. S. Emergency Planning and Community Right-to-Know Act, and is subject to reporting requirements by facilities which produce, store. The technical or chemical name of carbofuran is 2, 3-dihydro-2, 2-dimethyl-7-benzofuranyl methylcarbamate and it is manufactured by the reaction of methyl isocyanate with 2, 3-dihydro-2, 2-dimethyl-7-hydroxybenzofuran. Carbofuran is banned in Canada and the European Union, in 2008, the United States Environmental Protection Agency announced that it intends to ban carbofuran. In December of that year, FMC Corp, with this change, carbofuran usage in the US would be allowed only on maize, potatoes, pumpkins, sunflowers, pine seedlings and spinach grown for seed. However, in May 2009 EPA cancelled all food tolerances, an action which amounts to a de facto ban on its use on all crops grown for human consumption, Kenya is considering banning carbofuran, but it is legal to buy over-the-counter in Kenya. Carbofuran is highly toxic to vertebrates with an oral LD50 of 8–14 mg/kg in rats and 19 mg/kg in dogs, Carbofuran is known to be particularly toxic to birds. In its granular form, a grain will kill a bird. Birds often eat numerous grains of the pesticide, mistaking them for seeds, before the granular form was banned by U. S. Environmental Protection Agency in 1991, it was blamed for millions of bird deaths per year. The liquid version of the pesticide is less hazardous to birds since they are not as likely to ingest it directly, but it is still very hazardous. Carbofuran has been used to intentionally poison wildlife in the US, Canada and Great Britain, poisoned wildlife have included coyotes, kites, golden eagles. Secondary fatal poisoning of domestic and wild animals has been documented, specifically, raptors, domestic dogs, raccoons, vultures, in Kenya, farmers are using carbofuran to kill lions and other predators. In a number of publicized incidents worldwide, carbofuran has also used to poison domestic pets

15.
Ethienocarb
–
A carbamate is an organic compound derived from carbamic acid. A carbamate group, carbamate ester, and carbamic acids are functional groups that are inter-related structurally, carbamate esters are also called urethanes. Carbamic acids are derived from amines, R2NH + CO2 → R2NCO2H Carbamic acid is about as acidic as acetic acid, n-terminal amino groups of valine residues in the α- and β-chains of deoxyhemoglobin exist as carbamates. They help to stabilise the protein, when it becomes deoxyhemoglobin and this stabilizing effect should not be confused with the Bohr effect. The ε-amino groups of the residues in urease and phosphotriesterase also feature carbamate. The carbamate derived from aminoimidazole is an intermediate in the biosynthesis of inosine, carbamoyl phosphate is generated from carboxyphosphate rather than CO2. Perhaps the most important carbamate is the one involved in the capture of CO2 by plants since this process is necessary for their growth, the enzyme ribulose 1, 5-bisphosphate carboxylase/oxygenase fixes a molecule of carbon dioxide as phosphoglycerate in the Calvin cycle. At the active site of the enzyme, a Mg2+ ion is bound to glutamate and aspartate residues as well as a lysine carbamate. The carbamate is formed when an uncharged lysine side chain near the ion reacts with a carbon dioxide molecule from the air, which renders it charged. The so-called carbamate insecticides feature the carbamate ester functional group, included in this group are aldicarb, carbofuran, carbaryl, ethienocarb, fenobucarb, oxamyl, and methomyl. These insecticides kill insects by reversibly inactivating the enzyme acetylcholinesterase, the organophosphate pesticides also inhibit this enzyme, although irreversibly, and cause a more severe form of cholinergic poisoning. Fenoxycarb has a group but acts as a juvenile hormone mimic. The insect repellent icaridin is a substituted carbamate, polyurethanes contain multiple carbamate groups as part of their structure. The urethane in the name refers to these carbamate groups. In contrast, the commonly called urethane, ethyl carbamate, is neither a component of polyurethanes. Urethanes are usually formed by reaction of an alcohol with an isocyanate, commonly, urethanes made by a non-isocyanate route are called carbamates. Polyurethane polymers have a range of properties and are commercially available as foams, elastomers. Typically, polyurethane polymers are made by combining diisocyanates, e. g. Urethane was once produced commercially in the United States as an antineoplastic agent and it was found to be toxic and largely ineffective

16.
Oxamyl
–
Oxamyl is a chemical used as a pesticide that comes in two forms, granulated and liquid. The granulated form has been banned in the United States and it is commonly sold under the trade name Vydate. It is classified as a hazardous substance in the United States as defined in Section 302 of the U. S. Emergency Planning and Community Right-to-Know Act, and is subject to reporting requirements by facilities which produce, store. According to the WHO Food and Agriculture Organization, Oxamyl is a crystalline solid with a melting point of 100-102 °C changing to a dimorphic form with a melting point of 108-110 °C. It has a slightly sulfurous odour and it has a specific gravity of 0.97. Oxamyl is extremely toxic to humans whether ingested, inhaled, or contact with the skin and its overuse can also lead to residue accumulation in food, though its chemical composition—once coming into contact with the soil—rapidly degrades. According to the Food and Agriculture Organization, Contact with the skin, inhalation of dust or spray, or swallowing may be fatal. Because of its toxicity, its use is restricted in the EU/UK with maximum residue limits for apples and oranges being 0.01 mg/kg, Oxamyl in the Pesticide Properties DataBase

17.
Methomyl
–
Methomyl is a carbamate insecticide introduced in 1966. It is highly toxic to humans, livestock, pets, the EU and UK imposed a pesticide residue limit of 0.02 mg/kg for apples and oranges. Off-label uses and other uses not specifically targeted at problem insects are illegal, dangerous, methomyl is a broad-spectrum insecticide that is used to kill insect pests. Common names for methomyl include metomil and mesomile and it is in lower Toxicity Categories for inhalation, acute dermal effects, and acute skin irritation. Methomyl is not likely to be a carcinogen, methomyl has low persistence in the soil environment, with a reported half-life of approximately 14 days. Because of its solubility in water, and low affinity for soil binding methomyl may have potential for groundwater contamination. The estimated aqueous half-life for the insecticide is 6 days in water and over 25 weeks in groundwater. Methomyl can be produced by reaction of methyl isocyanate and methylthioacetaldoxime, first prepare ester Second prepare oxime from ester Third prepare product from isocyanate and oxime. Methomyl in the Pesticide Properties DataBase

18.
Propoxur
–
Propoxur is a carbamate insecticide and was introduced in 1959. Propoxur is a non-systemic insecticide with a fast knockdown and long residual effect used against turf, forestry and it is also used in pest control for other domestic animals, Anopheles mosquitoes, ants, gypsy moths, and other agricultural pests. It can also be used as a molluscicide, several U. S. Carbamate insecticides kill insects by reversibly inactivating the enzyme acetylcholinesterase. It rapidly breaks down in alkaline solution, propoxur is highly toxic to many bird species, but its toxicity varies by the species. It is moderately to slightly toxic to fish and other aquatic species, propoxur is highly toxic to honeybees

19.
Aluminium phosphide
–
Aluminium phosphide is a highly toxic inorganic compound with the chemical formula AlP used as a wide band gap semiconductor and a fumigant. This colorless solid is generally sold as a grey-green-yellow powder due to the presence of impurities arising from hydrolysis, AlP crystals are dark grey to dark yellow in color and have a zincblende crystal structure with a lattice constant of 5.4510 Å at 300 K. They are thermodynamically stable up to 1,000 °C, AlP is used as a rodenticide, insecticide, and fumigant for stored cereal grains. It is used to kill small mammals such as moles. AlP is used as both a fumigant and an oral pesticide, as a rodenticide, aluminium phosphide pellets are provided as a mixture with food for consumption by the rodents. The acid in the system of the rodent reacts with the phosphide to generate the toxic phosphine gas. Other pesticides similar to aluminium phosphide are zinc phosphide and calcium phosphide, in this application, aluminium phosphide can be encountered under various brand names, e. g. Celphos, Fostox, Fumitoxin, Phostek, Phostoxin, Quick Phos, Talunex, and Weevil-Cide. It generates phosphine gas according to the following hydrolysis equation, all of these structures can be effectively sealed or enclosed in a gastight membrane, thereby containing and concentrating the phosphine fumes. Fumigants are also applied directly to rodent burrows, industrially, AlP is a semiconductor material that is usually alloyed with other binary materials for applications in devices such as light-emitting diodes. Highly poisonous, aluminium phosphide has been used for suicide, fumigation has also caused unintentional deaths, such as examples in Saudi Arabia and the United States. Known as rice tablet in Iran, for its use to preserve rice, there is a campaign by the Iranian Forensic Medicine Organization to stop its use as a pesticide. Recycling of used aluminium phosphide containers caused the death of three members in Alcalá de Guadaira, Spain. They had been keeping them in sacks in their bathroom. The deaths occurred due to aluminum phosphide reacting with water or moisture. Aluminium phosphide poisoning is considered a problem in the Indian subcontinent

20.
Boric acid
–
It has the chemical formula H3BO3, and exists in the form of colorless crystals or a white powder that dissolves in water. When occurring as a mineral, it is called sassolite, Boric acid, or sassolite, is found mainly in its free state in some volcanic districts, for example, in the Italian region of Tuscany, the Lipari Islands and the US state of Nevada. In these volcanic settings it issues, mixed with steam, from fissures in the ground and it is also found as a constituent of many naturally occurring minerals – borax, boracite, ulexite and colemanite. Boric acid and its salts are found in seawater and it is also found in plants, including almost all fruits. Boric acid was first prepared by Wilhelm Homberg from borax, by the action of mineral acids, however borates, including boric acid, have been used since the time of the Greeks for cleaning, preserving food, and other activities. When heated above 170 °C, it dehydrates, forming metaboric acid, H3BO3 → HBO2 + H2O Metaboric acid is a white, further heating leads to boron trioxide. H2B4O7 →2 B2O3 + H2O There are conflicting interpretations for the origin of the acidity of aqueous boric acid solutions, polyborate anions are formed at pH 7–10 if the boron concentration is higher than about 0.025 mol/L. The best known of these is the ion, found in the mineral borax. With polyols such as glycerol and mannitol the acidity of the solution is increased, with mannitol for example the pK decreases to 5.15. This is due to the formation of a chelate, −, Boric acid dissolves in anhydrous sulfuric acid, B3 + 6H2SO4 → 3H3O+ + 2HSO4− + B4− Boric acid reacts with alcohols to form borate esters, B3 where R is alkyl or aryl. A dehydrating agent, such as concentrated sulfuric acid is typically added, the B-O bond length is 136 pm and the O-H is 97 pm. The molecular point group is C3h, crystalline boric acid consists of layers of B3 molecules held together by hydrogen bonds of length 272 pm. The distance between two adjacent layers is 318 pm, based on mammalian median lethal dose rating of 2,660 mg/kg body mass, boric acid is only poisonous if taken internally or inhaled in large quantities. The Fourteenth Edition of the Merck Index indicates that the LD50 of boric acid is 5.14 g/kg for oral dosages given to rats, for comparisons sake, the LD50 of salt is reported to be 3.75 g/kg in rats according to the Merck Index. Humans have been known to die from amounts only a fraction of the LD50. Long term exposure to acid may be of more concern, causing kidney damage. Although it does not appear to be carcinogenic, studies in dogs have reported testicular atrophy after exposure to 32 mg/kg bw/day for 90 days and this level is far lower than the LD50. As a consequence, in August 2008, in the 30th ATP to EU directive 67/548/EEC, textile fiberglass is used to reinforce plastics in applications that range from boats, to industrial piping to computer circuit boards

21.
Copper(II) arsenate
–
Its CAS number is 7778-41-8 or 10103-61-4. Copper arsenate is a used in agriculture. It is also used as a herbicide, fungicide, and a rodenticide and it is also used as a poison in slug baits. Copper arsenate can also be a misnomer for copper arsenite, especially when meant as a pigment, anhydrous copper arsenate, Cu32, is found in nature as the mineral lammerite. Copper arsenate tetrahydrate, Cu32. 4H2O, occurs naturally as the mineral rollandite, Copper arsenate hydroxide or basic copper arsenate is a basic variant with CAS number 16102-92-4. It is found naturally as the mineral olivenite and it is used as an insecticide, fungicide, and miticide. Its use is banned in Thailand since 2001, lead arsenate Calcium arsenate Paris Green Chromated copper arsenate Scheeles Green National Pollutant Inventory - Copper and compounds fact sheet

22.
Copper(I) cyanide
–
Copper cyanide is an inorganic compound with the formula CuCN. This off-white solid occurs in two polymorphs, impure samples can be due to the presence of Cu impurities. The compound is useful as a catalyst, in electroplating copper, Copper cyanide is a coordination polymer. It exists in two polymorphs both of which contain -- chains made from linear copper centres linked by cyanide bridges. In the high-temperature polymorph, HT-CuCN, which is isostructural with AgCN, in the low-temperature polymorph, LT-CuCN, the chains deviate from linearity and pack into rippled layers which pack in an AB fashion with chains in adjacent layers rotated by 49 °, Figure 2. LT-CuCN can be converted to HT-CuCN by heating to 563 K in an inert atmosphere, in both polymorphs the copper to carbon and copper to nitrogen bond lengths are ~1.85 Å and bridging cyanide groups show head-to-tail disorder. Cuprous cyanide is commercially available and is supplied as the low-temperature polymorph and it can be prepared by the reduction of copper sulfate with sodium bisulfite at 60 °C, followed by the addition of sodium cyanide to precipitate pure LT-CuCN as a pale yellow powder. 2 CuSO4 + NaHSO3 + H2O +2 NaCN →2 CuCN +3 NaHSO4 On addition of sodium bisulfite the copper sulfate solution turns blue to green. The reaction is performed under acidic conditions. The similarity of this reaction to that between copper sulfate and sodium iodide to form copper iodide is one example of cyanide ions acting as a pseudo halide and it also explains why copper cyanide, Cu2, has not been synthesised. Copper cyanide is insoluble in water but rapidly dissolves in solutions containing CN− to form 2− and 3− and these complexes contrast with those of silver and gold cyanides, which form − ions in solution. The coordination polymer KCu2 contains − units, which link together forming helical anionic chains, Copper cyanide is also soluble in concentrated aqueous ammonia, pyridine and N-methylpyrrolidone. Cuprous cyanide is used for electroplating copper, CuCN is a prominent reagent in organocopper chemistry. It reacts with organolithium reagents to form mixed cuprates with the formulas Li, the use of CuCN revolutionized the deployment of simpler organocopper reagents of the type CuR and LiCuR2, the so-called Gilman reagents. In the presence of cyanide, these cuprates are more readily purified. The mixed cuprates Li and Li2 function as sources of the carbanions R−, thus they are useful for conjugate additions and some displacement reactions. Addition of CuCN to CuCN also forms silyl and stannyl reagents, CuCN is used in the conversion of aryl halides to nitriles. National Pollutant Inventory - Cyanide compounds fact sheet National Pollutant Inventory - Copper and compounds fact sheet

23.
Diatomaceous earth
–
Diatomaceous earth, also known as D. E. diatomite, or kieselgur/kieselguhr, is a naturally occurring, soft, siliceous sedimentary rock that is easily crumbled into a fine white to off-white powder. It has a size ranging from less than 3 micrometres to more than 1 millimetre. Depending on the granularity, this powder can have a feel, similar to pumice powder. The typical chemical composition of oven-dried diatomaceous earth is 80 to 90% silica, Diatomaceous earth consists of fossilized remains of diatoms, a type of hard-shelled algae. Each deposit of diatomaceous earth is different, with varying blends of pure diatomaceous earth combined with other natural clays, the diatoms in each deposit contain different amounts of silica, depending on the age of the deposit. The species of diatom may also differ among deposits, the species of diatom is dependent upon the age and paleo-environment of the deposit. In turn, the shape of a diatom is determined by its species, many deposits throughout British Columbia, Canada, such as Red Lake Earth, are from the Miocene age and contain a species of diatom known as Melosira granulata. These diatoms are approximately 12 to 13 million years old and have a globular shape. A deposit containing diatoms from this age can provide more benefits than that of an older deposit. For example, diatoms from the Eocene age are not as effective in their ability to absorb fluids because older diatoms recrystallize, Diatomite forms by the accumulation of the amorphous silica remains of dead diatoms in lacustrine or marine sediments. The fossil remains consist of a pair of shells or frustules. In 1836 or 1837, the peasant and goods waggoner Peter Kasten discovered diatomaceous earth when sinking a well on the slopes of the Haußelberg hill. Initially, it was thought that limestone had been found, which could be used as fertilizer, until the First World War almost the entire worldwide production of diatomaceous earth was from this region. In Germany, diatomaceous earth was also extracted at Altenschlirf on the Vogelsberg, there is a layer of diatomaceous earth up to 4 metres thick in the nature reserve of Soos in the Czech Republic. Deposits on the isle of Skye, off the west coast of Scotland, were mined until 1960, in Colorado and in Clark County, Nevada, United States, there are deposits that are up to several hundred metres thick in places. Marine deposits have been worked in the Sisquoc Formation in Santa Barbara County, California near Lompoc, additional marine deposits have been worked in Maryland, Virginia, Algeria and the MoClay of Denmark. Freshwater lake deposits occur in Nevada, Oregon, Washington and California, Lake deposits also occur in interglacial lakes in the eastern United States, in Canada and in Europe in Germany, France, Denmark and the Czech Republic. The worldwide association of diatomite deposits and volcanic deposits suggests that the availability of silica from volcanic ash may be necessary for thick diatomite deposits, sometimes diatomaceous earth is found on the surfaces of deserts

24.
Paris Green
–
Paris green is an inorganic compound. It is a highly toxic emerald-green crystalline powder that has used as a rodenticide and insecticide. It is also used as a colorant for fireworks. The color of Paris green is said to range from a blue green when very finely ground. Paris green may be prepared by combining acetate and arsenic trioxide. Paris green was used to kill rats in Parisian sewers. It was also used in America and elsewhere as an insecticide for produce such as apples, around 1900 and this toxic mixture is said to have burned the trees and the grass around the trees. Paris green was heavily sprayed by airplane in Italy, Sardinia, similar natural compounds are the minerals chalcophyllite Cu 18Al 233 27·36H 2O, conichalcite CaCu, cornubite Cu 52 4·H 2O, cornwallite Cu 52 4·H 2O, and liroconite Cu 2Al 4·4H 2O. These vivid minerals range from blue to slightly yellowish green. It was popular as a pigment and would degrade, with moisture and molds. Paris green may have also used in wallpaper to some extent. Both pigments were used in printing ink formulations. The ancient Romans used one of them, possibly conichalcite, as a green pigment, the Paris green paint used by the Impressionists is said to have been composed of relatively coarse particles. Later, the chemical was produced with increasingly small grinds and without carefully removing impurities and it is likely that it was ground more finely for use in watercolors and inks, too

25.
Scheele's Green
–
Scheeles Green, also called Schloss Green, is chemically a cupric hydrogen arsenite, CuHAsO3. It is chemically related to Paris Green, Scheeles Green was invented in 1775 by Carl Wilhelm Scheele. By the end of the 19th century, it replaced the older green pigments based on copper carbonate. This produced a sodium arsenite solution, added to a copper sulfate solution, it produced a green precipitate of effectively insoluble copper arsenite. After filtration the product was dried at about 43 °C, to enhance the color, the salt was subsequently heated to 60–70 °C. The intensity of the color depends on the copper, arsenic ratio, Scheeles Green was used as a color for paper, e. g. for wallpapers and paper hangings, and in paints, wax candles, and even on some childrens toys. It was also used to dye cotton and linen, Scheeles Green is more brilliant and durable than the then-used copper carbonate pigments. However, because of its content it tends to fade and blacken when exposed to sulfides. Emerald green, also known as Paris Green, was developed later in attempt to improve Scheeles Green and it had the same tendency to blacken, but was more durable. By the end of 19th century, both greens were made obsolete by cobalt green, also known as green, which is far less toxic. Scheeles Green was used as an insecticide in the 1930s, together with Paris Green, in the 19th century the toxicity of arsenic compounds was not readily known. 19th century journals reported of children wasting away in bright green rooms, of ladies in green dresses swooning, there is one example of an acute poisoning of children attending a Christmas party where dyed candles were burned. Two main theories on the cause of wallpaper poisoning events have been proposed, dust particles caused by pigment and paper flaking, tiny particles of the pigment can flake off and become airborne, and then are absorbed by the lungs. Alternatively, toxic gas can be released from compounds containing arsenic following certain chemical processes, such as heating, when the wallpaper becomes damp and moldy, the pigment may be metabolised, causing the release of poisonous arsine gas. Fungi genera such as Scopulariopsis or Paecilomyces release arsine gas, when they are growing on a substance containing arsenic, in 1893 the Italian physician Bartolomeo Gosio published his results on Gosio gas that was subsequently shown to contain trimethylarsine. In these compounds, the arsenic is either pentavalent or trivalent, in humans, arsenic of these valences is readily absorbed by the gastrointestinal tract, which accounts for its high toxicity. However, newer studies indicate that trimethylarsine has a low toxicity and could not account for the death. Arsenic is not only toxic, but it also has carcinogenic effects, during Napoleons exile in St. Helena, he resided in a house in which the rooms were painted bright green, his favorite color

26.
Benzoylurea
–
Benzoylureas are chemical derivatives of N-benzoyl-N′-phenylurea. They are best known for their use as insecticides and they act as insect growth regulators by inhibiting synthesis of chitin in the insects body. One of the commonly used benzoylurea pesticides is diflubenzuron. Others include chlorfluazuron, flufenoxuron, hexaflumuron, and triflumuron, lufenuron is the active compound in flea control medication for pet dogs and cats. Certain types of compounds have been investigated as potential anticancer agents. Flufenoxuron was banned in the European Union in 2011 due to its potential for bioaccumulation in the food chain. Flufenoxuron is marketed as having high persistence in the environment and the product data-sheet states that it does not biodegrade easily

27.
Diflubenzuron
–
Diflubenzuron is a benzoylurea-type insecticide of the benzamide class. It is used in forest management and on field crops to control insect pests, particularly forest tent caterpillar moths, boll weevils, gypsy moths. Diflubenzuron has been evaluated by the United States Environmental Protection Agency, while 4-Chloroaniline, a metabolite of diflubenzuron, has been classified as a Carcinogen, it is not present in diflubenzuron. 4-Chloroaniline is produced after diflubenzuron has been ingested, and the changes a small fraction of it to the metabolite. Diflubenzuron has been tested, and the small amount converted to 4-chloroaniline after ingestion does not cause cancer

28.
Lufenuron
–
Lufenuron is stored in the animals body fat and transferred to adult fleas through the hosts blood when they feed. Adult fleas transfer it to their eggs through their blood. It does not kill adult fleas, lufenuron, a benzoylurea pesticide, inhibits the production of chitin in insects. Without chitin, a larval flea will never develop an outer shell. With its inner organs exposed to air, the dies from dehydration soon after hatching or molting. Lufenuron is also used to fight infections, since fungus cell walls are about one third chitin. Lufenuron is also sold as a pesticide for use against lepidopterans, eriophid mites. It is an effective antifungal in plants, lufenuron in the Pesticide Properties DataBase

29.
Pyriproxyfen
–
Pyriproxyfen is a pyridine-based pesticide which is found to be effective against a variety of arthropoda. It was introduced to the US in 1996, to cotton crops against whitefly. It has also found useful for protecting other crops. It is also used as a prevention for flea control on household pets, for killing indoor and outdoor ants, methods of application include aerosols, bait, carpet powders, foggers, shampoos and pet collars. Pyriproxyfen is a juvenile hormone analog and a growth regulator. It prevents larvae from developing into adulthood and thus rendering them unable to reproduce, in the US, pyriproxyfen is often marketed under the trade name Nylar. In Europe, pyriproxyfen is known under the brand names Cyclio, according to WHO and FAO, at elevated doses exceeding 5000 mg/kg of body weight, pyriproxyfen affects the liver in mice, rats and dogs. It also changes cholesterol levels, and may cause modest anemia at high doses, starting in 2014, pyriproxifen was put into Brazilian water supplies to fight the proliferation of mosquito larvae. This is in line with the World Health Organization s Pesticide Evaluation Scheme for larvicides, in January 2016, the Brazilian Association for Collective Health criticized the introduction of pyriproxyfen in Brazil. Abrasco demanded the suspension of pyriproxyfen and all growth inhibitors. The organization is opposed to the use of growth inhibitors in the context of an outbreak of fetal malformation. They also condemned the behavior of the websites that spread the misinformation, adding that such untruths. violates the anguish, on February 13, the Brazilian state of Rio Grande do Sul suspended pyriproxyfens use, citing both Abrasco and PCST positions. The Health Minister of Brazil, Marcelo Castro, criticized this step, noting that the claim is a rumor lacking logic and they also noted that the insecticide is approved by the National Sanitary Monitoring Agency and all regulatory agencies in the whole world. He added that this lack of spatial correlation weakens the idea that the larvicide is the cause of the problem, in addition, the BBC interviewed researchers in Pernambuco, where no evidence has been found of the cases being linked to any environmental cause like an insecticide. A professor from the University of Adelaide in Australia, stated that The effect of pyriproxyfen on reproduction, in a variety of animal species even enormous quantities of pyriproxyfen do not cause the defects seen during the recent Zika outbreak. Methoprene Pyriproxyfen in the Pesticide Properties DataBase

30.
Neonicotinoid
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Neonicotinoids are a class of neuro-active insecticides chemically similar to nicotine. In the 1980s Shell and in the 1990s Bayer started work on their development, the neonicotinoid family includes acetamiprid, clothianidin, imidacloprid, nitenpyram, nithiazine, thiacloprid and thiamethoxam. Imidacloprid is the most widely used insecticide in the world, compared to organophosphate and carbamate insecticides neonicotinoids cause less toxicity in birds and mammals than insects. Some breakdown products are toxic to insects. In the late 1990s neonicotinoids came under increasing scrutiny over their environmental impact, neonicotinoid use was linked in a range of studies to adverse ecological effects, including honey-bee colony collapse disorder and loss of birds due to a reduction in insect populations. In 2013, the European Union and a few non EU countries restricted the use of certain neonicotinoids, in 1984 nithiazines mode of action was found to be as a postsynaptic acetylcholine receptor agonist, the same as nicotine. Nithiazine does not act as an inhibitor, in contrast to the organophosphate and carbamate insecticides. While nithiazine has the specificity, it is not photostable—that is, it breaks down in sunlight. In 1985, Bayer patented imidacloprid as the first commercial neonicotinoid, during the late 1990s, primarily, imidacloprid became widely used. Beginning in the early 2000s, two other neonicotinoids, clothianidin and thiamethoxam, entered the market, as of 2013, virtually all corn planted in the United States was treated with one of these two insecticides and various fungicides. As of 2014, about a third of US soybean acreage was planted with neonicotinoid-treated seeds, neonicotinoids have been registered in more than 120 countries. With a global turnover of €1.5 billion in 2008, after the introduction of the first neonicotinoids in the 1990s, this market has grown from €155 million in 1990 to €957 million in 2008. Neonicotinoids made up 80% of all seed treatment sales in 2008, as of 2011, seven neonicotinoids from different companies are on the market. Imidacloprid is effective against sucking insects, some chewing insects, soil insects and it is systemic with particular efficacy against sucking insects and has a long residual activity. Imidacloprid can be added to the used to irrigate plants. Controlled release formulations of imidacloprid take 2–10 days to release 50% of imidacloprid in water and it is applied against soil pests, seed, timber and animal pests as well as foliar treatments. As of 2013 neonicotinoids have been used In the U. S. on about 95 percent of corn and canola crops, the majority of cotton, sorghum, imidacloprid is possibly the most widely used insecticide, both within the neonicotinoids and in the worldwide market. In agriculture, usefulness of neonicotinoid seed treatments for pest prevention depends upon the timing of planting, neonicotinoid seed treatments can protect yield in special cases such as late-planted fields or in areas with large infestations much earlier in the growing season

31.
Dinotefuran
–
Its mechanism of action involves disruption of the insects nervous system by inhibiting nicotinic acetylcholine receptors. In order to avoid harming beneficial insects such as bees, it should not be applied during bloom, in July 2013, the state of Oregon temporarily restricted the use of dinotefuran pending the results of an investigation into a large bee kill. Dinotefuran is also used in medicine as a flea and tick preventative for dogs. It is used in combination with pyriproxifen or permethrin

32.
Imidacloprid
–
The chemical works by interfering with the transmission of stimuli in the insect nervous system. Specifically, it causes a blockage of the nicotinergic neuronal pathway, by blocking nicotinic acetylcholine receptors, imidacloprid prevents acetylcholine from transmitting impulses between nerves, resulting in the insects paralysis and eventual death. It is effective on contact and via stomach action, because imidacloprid binds much more strongly to insect neuron receptors than to mammal neuron receptors, this insecticide is more toxic to insects than to mammals. As of 1999, Imidacloprid was the most widely used insecticide in the world, although it is now off patent, the primary manufacturer of this chemical is Bayer CropScience. Imidacloprid is widely used for pest control in agriculture, as a result, several countries have restricted use of imidacloprid and other neonicotinoids. Imidacloprid is the most widely used insecticide in the world, when used on trees, it can take 30–60 days to reach the top and enter the leaves in high enough quantities to be effective. Imidacloprid can be found in the trunk, the branches, the twigs, the leaves, the leaflets, and the seeds. But others such as trees, linden, catalpa, and black locust trees are bee and wind pollinated. Higher doses must be used to control boring insects than other types, on January 21,1986 a patent was filed, and granted on May 3,1988, for imidacloprid in the United States by Nihon Tokushu Noyaku Seizo K. K. of Tokyo, Japan. On March 25,1992, Miles, Inc. applied for registration of imidacloprid for turfgrass, on March 10,1994, the U. S. Environmental Protection Agency approved the registration of imidacloprid. On January 26,2005, the Federal Register notes the establishment of the Emergency Exemptions for imidacloprid and it use was granted to Hawaii use this pesticide on bananas and the States of Minnesota, Nebraska, and North Dakota to use this pesticide on sunflower. Imidacloprid is a systemic pesticide, belonging to the class of neonicotinoid insecticides. It works by interfering with the transmission of nerve impulses in insects by binding irreversibly to specific insect nicotinic acetylcholine receptors. As a systemic pesticide, imidacloprid translocates or moves easily in the xylem of plants from the soil into the leaves, fruit, pollen, Imidacloprid also exhibits excellent translaminar movement in plants and can penetrate the leaf cuticle and move readily into leaf tissue. Since imidacloprid is efficacious at very low levels, it can be applied at lower concentrations than other insecticides, the main routes of dissipation of imidacloprid in the environment are aqueous photolysis and plant uptake. The major photometabolites include imidacloprid desnitro, imidacloprid olefine, imidacloprid urea, the end product of photodegradation is chloronicotinic acid and ultimately carbon dioxide. Since imidacloprid has a low pressure, it normally does not volatilize readily. Although imidacloprid breaks down rapidly in water in the presence of light and it has a water solubility of.61 g/L, which is relatively high

33.
Nitenpyram
–
Nitenpyram is an insecticide used in agriculture and veterinary medicine to kill external parasites of pets. It is a neonicotinoid, a neurotoxin that blocks neural messages and binds particularly tightly in the nervous system of insects. It has been used orally in dogs, cats and some species for over 10 years. After ingestion, it begins killing adult fleas within 10 to 30 minutes and continues to kill fleas for 4 to 6 hours, the effects of nitenpyram last approximately 24–48 hours. Nitenpyram is safe to use on puppies and kittens as young as four weeks old if they weigh at least 2 pounds, panting and excitement, as well as other symptoms, have been noted in cats and dogs within 2 hours of administration. In heavily infested animals, it can cause extreme itching as the fleas die, there is no antidote for Nitenpyram poisoning. Nitenpyram does not kill insect eggs and has no long-term activity, thus, it is not effective as a long-term flea preventative. It is used to kill adult fleas quickly on an infested animal, Nitenpyram in the Pesticide Properties DataBase Capstar website Material Safety Data Sheet for Nitenpyram Freedom of Information summary, US Food and Drug Administration

ChemSpider
–
ChemSpider is a database of chemicals. ChemSpider is owned by the Royal Society of Chemistry, the database contains information on more than 50 million molecules from over 500 data sources including, Each chemical is given a unique identifier, which forms part of a corresponding URL. This is an approach to develop an online chemistry database. The

1.
ChemSpider

Chemical formula
–
These are limited to a single typographic line of symbols, which may include subscripts and superscripts. A chemical formula is not a name, and it contains no words. Although a chemical formula may imply certain simple chemical structures, it is not the same as a full chemical structural formula. Chemical formulas can fully specify the structure of

1.
Al 2 (SO 4) 3

Density
–
The density, or more precisely, the volumetric mass density, of a substance is its mass per unit volume. The symbol most often used for density is ρ, although the Latin letter D can also be used. Mathematically, density is defined as mass divided by volume, ρ = m V, where ρ is the density, m is the mass, and V is the volume. In some cases, density

1.
Air density vs. temperature

Vapor pressure
–
Vapor pressure or equilibrium vapor pressure is defined as the pressure exerted by a vapor in thermodynamic equilibrium with its condensed phases at a given temperature in a closed system. The equilibrium vapor pressure is an indication of a liquids evaporation rate and it relates to the tendency of particles to escape from the liquid. A substance

1.
Graph of water vapor pressure versus temperature. At the normal boiling point of 100 °C, it equals the standard atmospheric pressure of 760 Torr or 101.325 kPa.

2.
The picture shows the particle transition, as a result of their vapor pressure, from the liquid phase to the gas phase and converse.

Pyrethroid
–
A pyrethroid is an organic compound similar to the natural pyrethrins produced by the flowers of pyrethrums. Pyrethroids now constitute the majority of commercial household insecticides, pyrethroids are axonic excitoxins, the toxic effects of which are mediated through preventing the closure of the voltage-gated sodium channels in the axonal membra

1.
Allethrin

Insecticide
–
An insecticide is a substance used to kill insects. They include ovicides and larvicides used against insect eggs and larvae, Insecticides are used in agriculture, medicine, industry and by consumers. Insecticides are claimed to be a factor behind the increase in agricultural 20th centurys productivity. Nearly all insecticides have the potential to

1.
FLIT manual spray pump for insecticides from 1928

2.
Pesticide types

3.
Extant

Enantiomer
–
A single chiral atom or similar structural feature in a compound causes that compound to have two possible structures which are non-superposable, each a mirror image of the other. Each member of the pair is termed an enantiomorph, the property is termed enantiomerism. The presence of multiple features in a given compound increases the number of geo

1.
(S)-(+)- lactic acid (left) and (R)-(–)-lactic acid (right) are nonsuperposable mirror images of each other

Fenvalerate
–
It is a mixture of four optical isomers which have different insecticidal activities. The 2-S alpha configuration, known as esfenvalerate, is the most insecticidally active isomer, fenvalerate consists of about 23% of this isomer. Fenvalerate is an insecticide of moderate mammalian toxicity, in laboratory animals, central nervous system toxicity is

1.
Fenvalerate

Pest control
–
Pest control refers to the regulation or management of a species defined as a pest, and can be perceived to be detrimental to a persons health, the ecology or the economy. A practitioner of pest control is called an exterminator, Pest control is at least as old as agriculture, as there has always been a need to keep crops free from pests. In order

1.
A crop duster applies low-insecticide bait that is targeted against Western corn rootworms.

2.
Sign in Ilfracombe, England designed to help control seagull presence

3.
Dog control van, Rekong Peo, Himachal Pradesh, India

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Rodent Bait Station, Chennai, India

Carbamate
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A carbamate is an organic compound derived from carbamic acid. A carbamate group, carbamate ester, and carbamic acids are functional groups that are inter-related structurally, carbamate esters are also called urethanes. Carbamic acids are derived from amines, R2NH + CO2 → R2NCO2H Carbamic acid is about as acidic as acetic acid, n-terminal amino gr

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Chemical structure of carbamates

Aldicarb
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Aldicarb is a carbamate insecticide which is the active substance in the pesticide Temik. It is effective against thrips, aphids, spider mites, lygus, fleahoppers, and leafminers, aldicarb is a cholinesterase inhibitor which prevents the breakdown of acetylcholine in the synapse. In case of poisoning, the victim dies of respiratory failure. Aldicar

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Aldicarb

Bendiocarb
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Bendiocarb is an acutely toxic carbamate insecticide used in public health and agriculture and is effective against a wide range of nuisance and disease vector insects. Many bendiocarb products are or were sold under the tradenames Ficam and Turcam and it is one of 12 insecticides recommended by the World Health Organization for use in malaria cont

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Bendiocarb

Carbaryl
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Carbaryl is a chemical in the carbamate family used chiefly as an insecticide. It is a crystalline solid commonly sold under the brand name Sevin. Union Carbide discovered carbaryl and introduced it commercially in 1958, Bayer purchased Aventis CropScience in 2002, a company that included Union Carbide pesticide operations. It remains the third-mos

Carbofuran
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Carbofuran is one of the most toxic carbamate pesticides. It is marketed under the trade names Furadan, by FMC Corporation and Curater and it is used to control insects in a wide variety of field crops, including potatoes, corn and soybeans. It is an insecticide, which means that the plant absorbs it through the roots. Carbofuran also has activity

Ethienocarb
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A carbamate is an organic compound derived from carbamic acid. A carbamate group, carbamate ester, and carbamic acids are functional groups that are inter-related structurally, carbamate esters are also called urethanes. Carbamic acids are derived from amines, R2NH + CO2 → R2NCO2H Carbamic acid is about as acidic as acetic acid, n-terminal amino gr

Oxamyl
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Oxamyl is a chemical used as a pesticide that comes in two forms, granulated and liquid. The granulated form has been banned in the United States and it is commonly sold under the trade name Vydate. It is classified as a hazardous substance in the United States as defined in Section 302 of the U. S. Emergency Planning and Community Right-to-Know Ac

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Oxamyl

Methomyl
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Methomyl is a carbamate insecticide introduced in 1966. It is highly toxic to humans, livestock, pets, the EU and UK imposed a pesticide residue limit of 0.02 mg/kg for apples and oranges. Off-label uses and other uses not specifically targeted at problem insects are illegal, dangerous, methomyl is a broad-spectrum insecticide that is used to kill

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Methomyl

Propoxur
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Propoxur is a carbamate insecticide and was introduced in 1959. Propoxur is a non-systemic insecticide with a fast knockdown and long residual effect used against turf, forestry and it is also used in pest control for other domestic animals, Anopheles mosquitoes, ants, gypsy moths, and other agricultural pests. It can also be used as a molluscicide

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Propoxur

Aluminium phosphide
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Aluminium phosphide is a highly toxic inorganic compound with the chemical formula AlP used as a wide band gap semiconductor and a fumigant. This colorless solid is generally sold as a grey-green-yellow powder due to the presence of impurities arising from hydrolysis, AlP crystals are dark grey to dark yellow in color and have a zincblende crystal

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Aluminium phosphide

Boric acid
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It has the chemical formula H3BO3, and exists in the form of colorless crystals or a white powder that dissolves in water. When occurring as a mineral, it is called sassolite, Boric acid, or sassolite, is found mainly in its free state in some volcanic districts, for example, in the Italian region of Tuscany, the Lipari Islands and the US state of

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Boric acid

Copper(II) arsenate
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Its CAS number is 7778-41-8 or 10103-61-4. Copper arsenate is a used in agriculture. It is also used as a herbicide, fungicide, and a rodenticide and it is also used as a poison in slug baits. Copper arsenate can also be a misnomer for copper arsenite, especially when meant as a pigment, anhydrous copper arsenate, Cu32, is found in nature as the mi

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Copper(II) arsenate

Copper(I) cyanide
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Copper cyanide is an inorganic compound with the formula CuCN. This off-white solid occurs in two polymorphs, impure samples can be due to the presence of Cu impurities. The compound is useful as a catalyst, in electroplating copper, Copper cyanide is a coordination polymer. It exists in two polymorphs both of which contain -- chains made from line

Diatomaceous earth
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Diatomaceous earth, also known as D. E. diatomite, or kieselgur/kieselguhr, is a naturally occurring, soft, siliceous sedimentary rock that is easily crumbled into a fine white to off-white powder. It has a size ranging from less than 3 micrometres to more than 1 millimetre. Depending on the granularity, this powder can have a feel, similar to pumi

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A sample of food-grade diatomaceous earth

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ca. 1900–1910 Diatomaceous earth pit at Neuohe

Paris Green
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Paris green is an inorganic compound. It is a highly toxic emerald-green crystalline powder that has used as a rodenticide and insecticide. It is also used as a colorant for fireworks. The color of Paris green is said to range from a blue green when very finely ground. Paris green may be prepared by combining acetate and arsenic trioxide. Paris gre

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Paris green

Scheele's Green
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Scheeles Green, also called Schloss Green, is chemically a cupric hydrogen arsenite, CuHAsO3. It is chemically related to Paris Green, Scheeles Green was invented in 1775 by Carl Wilhelm Scheele. By the end of the 19th century, it replaced the older green pigments based on copper carbonate. This produced a sodium arsenite solution, added to a coppe

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Scheele's Green

Benzoylurea
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Benzoylureas are chemical derivatives of N-benzoyl-N′-phenylurea. They are best known for their use as insecticides and they act as insect growth regulators by inhibiting synthesis of chitin in the insects body. One of the commonly used benzoylurea pesticides is diflubenzuron. Others include chlorfluazuron, flufenoxuron, hexaflumuron, and triflumur

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Chemical structure of diflubenzuron, a commonly used benzoylurea insecticide

Diflubenzuron
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Diflubenzuron is a benzoylurea-type insecticide of the benzamide class. It is used in forest management and on field crops to control insect pests, particularly forest tent caterpillar moths, boll weevils, gypsy moths. Diflubenzuron has been evaluated by the United States Environmental Protection Agency, while 4-Chloroaniline, a metabolite of diflu

Lufenuron
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Lufenuron is stored in the animals body fat and transferred to adult fleas through the hosts blood when they feed. Adult fleas transfer it to their eggs through their blood. It does not kill adult fleas, lufenuron, a benzoylurea pesticide, inhibits the production of chitin in insects. Without chitin, a larval flea will never develop an outer shell.

Pyriproxyfen
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Pyriproxyfen is a pyridine-based pesticide which is found to be effective against a variety of arthropoda. It was introduced to the US in 1996, to cotton crops against whitefly. It has also found useful for protecting other crops. It is also used as a prevention for flea control on household pets, for killing indoor and outdoor ants, methods of app

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Pyriproxyfen

Neonicotinoid
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Neonicotinoids are a class of neuro-active insecticides chemically similar to nicotine. In the 1980s Shell and in the 1990s Bayer started work on their development, the neonicotinoid family includes acetamiprid, clothianidin, imidacloprid, nitenpyram, nithiazine, thiacloprid and thiamethoxam. Imidacloprid is the most widely used insecticide in the

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R-nicotine (top) and desnitro-imidacloprid are both protonated in the body

Dinotefuran
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Its mechanism of action involves disruption of the insects nervous system by inhibiting nicotinic acetylcholine receptors. In order to avoid harming beneficial insects such as bees, it should not be applied during bloom, in July 2013, the state of Oregon temporarily restricted the use of dinotefuran pending the results of an investigation into a la

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Dinotefuran

Imidacloprid
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The chemical works by interfering with the transmission of stimuli in the insect nervous system. Specifically, it causes a blockage of the nicotinergic neuronal pathway, by blocking nicotinic acetylcholine receptors, imidacloprid prevents acetylcholine from transmitting impulses between nerves, resulting in the insects paralysis and eventual death.

Nitenpyram
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Nitenpyram is an insecticide used in agriculture and veterinary medicine to kill external parasites of pets. It is a neonicotinoid, a neurotoxin that blocks neural messages and binds particularly tightly in the nervous system of insects. It has been used orally in dogs, cats and some species for over 10 years. After ingestion, it begins killing adu